Separator for storage batteries



s a M a on ll altars GSCAEJ G. HIKE-LE AND ALVEN EAR-MES, OF- CAPE G'IRAFBJDEAU; MISSGUIEJ.

SEPARATGR F0371! STORAGE BATTERIES.

filpceification of Letters Patent.

No Application filed January 2, 1920. Serial No. 28,769.

V of Missouri, have invented certain new and useful improvements in Separator," for Storage Batteries of which the following is a specification.

This invention relates to separators for storage batteries, and to a process of pro ducing said separators, and it comprises a separator consisting of a wooden plate that has been exposed to boiling water at a high pressure, subjected to the action of super heated steam under high pressure, and treated with an aqueous solution of sulfuric acid; and it further comprises a method of producing such separators wherein a wooden plate is placed in boiling water undcr high pressure, then placed in a closed container and subjected to superheated steam under pressure, and then immersed in an aqueous solution ot sulfuric acid; all as more fully hereinafter set forth, and as claimed.

Separators for storage batteries are gcncrallymadc of wood or of rubber compo sition. They should be nonwouductivc, and

sulliciently porous to permit llow ot the electrolyte. ll? not suliiciently porous, the separators swell and warp causing them to split or c acl-:.

In the present inventii'm, we produce a scp arator for storage batteries in which the volatile chemical substances in the wood are removed by treatment with boiling water under high pressure and superheated steam under pressure, and in which the porosity of the plates is greatly increased by brcalc inc open the small cells in the wood by superheated steam.

in the present process the wooden plates are first placed in boiling wateiz at a tern-- pcrature of about 200" Cc, the boiling water removes some of the chemical substances that are hi hly volatile and which are ol jectioiuible in separators.

The plates are next passed through the steaming process wherein they are prefer-- ably placed in a closed container and sub jected to dry superheated steam under high pressure. This treatment removes the less volatile chemical substances which remain in the wooden plates after the treatment with boiling water and breaks open the small cells in the wood making a more porous separator which permits freer passage of the electrolytes between the plates of the battery. We have found that the stcain'treatment removes practically all the objectionable organic substances in the wood, but um'ler some conditions, it is ad-.

visable to immerse the platcs in an aqueous solution of sulfuric acid to dissolve and remove any remaining traces of the organic substances.

The above described process produces a. separator plate for storage batteries which is highly porous and which will not swell due to the presence of the electrolyte in the plate. The elimination of this tendency to swell also eliminates warping ol the plate and consequent splitting or cracking. The treatment with boiling ware and the steam treatment remove the volatile organic substances present in the wood which are objectionable in a storage battery.

il'hilc we have described an advantageous embodiment olour invention, it is apparent. that slight changes may be resorted to in pertorminr the process and the above de scription is meant to bc illustrative rather than restrictive.

ll hat we claim is:

l. The method of making separators for storage batteries which comprises subject mg a wooden plate to boiling water under high pressure, subjecting said plate to super? heated steam under high pressure. and then immersing said plate in an aqueous solution oi sulfuric acid.

2. The method of making separators for storage battcrics which comprises subject ing a wooden plate to superheated steam under high pressure, and then immersing said plate in an aqueous solution oi sulfuric acid.

ous said separator comprisingfln wooden plate that has been sub ected to boiling water under high pressure, then to super ll. sepa 'ator for storage batteries. formed of wood and being relatively por tlil' Elli Illlll heated steam under high pressure, and then In testimony whereof We aflix our signato'an aqueous solution of sulfuric acid. tures in presence of two Witnesses.

4. A separator for storage batteries R HIRQCH formed of wood and being relatively por- ALVIN P F 5 ous, said separator comprising a wooden plate that has been subjected to super- \Vitnesses: heated steam under high pressure, and then CHRIS J. HIRSCH,

to an aqueous solution of sulfuric acid. W. H. OBERHEIDE. 

